To increase the output and efficiency of motor vehicle air-conditioning systems, air-conditioning system-internal heat exchangers, so-called internal heat exchangers (IHX) are known, which thermally couple a section of the refrigerant circuit running between evaporator and compressor with a section of the refrigerant circuit running between condenser and expansion valve. In this manner the relatively cold refrigerant flowing from the evaporator to the compressor can be utilized for (pre-) cooling or sub-cooling of the comparatively warm refrigerant fed to the expansion device on the high-pressure side of the refrigerant circuit.
Thus, DE 10 2005 052 972 A1 for example describes a double-walled heat exchanger tube with an outer tube and an inner tube defining a channel between them. Here, the high-pressure refrigerant flows through the channel and the low-pressure refrigerant flows through the inner tube.
To optimize the manner of operation of such heat exchangers in the refrigerant circuit the geometrical dimensions and designs of the tubes are of overriding importance. In an existing vehicle package, which hardly offers room for the individual adaptation or changing of the outer contour or outer geometry of the heat exchanger, it is relatively difficult to individually, such as vehicle type specifically, adapt such heat exchangers with respect to their heat exchanger capacity to predetermined requirements.
Heat exchanger configurations which are known and described for example in DE 10 2005 052 972 A1 provide for example extruded or two-part section tubes with a substantially unchanged heat exchanger area in section longitudinal direction, which in this respect, dependent on the length and the diameter of the tubes, in each case can only transfer or exchange a constant amount of heat that remains the same at all times.
Compared with this, at least one object is to provide a heat exchanger with predetermined outer dimensions and outer contours which on the one hand provides an improved degree of thermal energy transfer between high-pressure side and low-pressure side of the refrigerant circuit and which on the other hand can be adapted with respect to its heat transfer or heat exchange capacity as variably and easily as possible to predetermined thermal requirements. In addition, the heat exchanger is to be characterized by low manufacturing costs and make possible a simple as well as intuitive installation. In addition, other objects, desirable features and characteristics will become apparent from the subsequent summary and detailed description, and the appended claims, taken in conjunction with the accompanying drawings and this background.